Saber type jigsaw blade



l pril 21, 1953 A. NoRQulsT SABER TYPE JIGsAw BLADE Filed bot. 2o; `194'? 2,. Alu/'n /Vor l INVENTOR.

- y' Il 5 BYZfQ-@MP ATTORNEYQ Patented Apr. 21%1953 UNITED STATES-'1 PATENT] oFFlcEr 3 V2,635,652 SABER TYPE JIGSAWBLADE Alvin Norquist, seattle, Wash. v Application october-20, 1947, seriai No. isaeis u n YThis inventionlrelates to jig-saws, and for its general" object aims to provide a perfected jig-sawA of inexpensive and simplerconstruction and one which, while applicable to general work, ,Y

peculiarly adapts itself `'to a quick and `accurate cutting of balsa and other wood or-cardboard materials employed by model makers in the production of small-scale airplanes, vessels and the like.

Ihe invention has the further and important object of providing a'new type of cutting blade and one, more especially, which is sectionally of a substantially square shape presenting cutting teeth upon each of the four sides thereof and thus enabling'the'blade to traverse sharp-angle turns. I It is further object still' to provide a jig-saw including the usual work-supporting table and characterized vinr that the vblade has sufficient rigidity to enable the same yto be supported from belowthistable only, with the working plane being consequently left entirely free of any obstruction to permit thework to be freely manipulated regardless'of'the length of the board being sawed.`

With the foregoing and other objects and advantages in view and which will appear and be understood in the course of the following de-V scription iandclaims, the invention consists in the novel construction and in the adaptation and combination of parts hereinafter described and claimed.

In the drawing:

Figure 1 is a side elevational view illustrating a jig-saw constructed in accordance with the preferred embodiment of the present invention.

Fig. 2 is a front elevational view thereof.

Fig. 3 is a top plan view with parts broken away and shown in section; and

Fig. 4 is a fragmentary longitudinal vertical sectional view taken to an enlarged scale on line 4 4 of Fig. 3.

According to the present invention there is provided a machine standard designated by the 2 Claims. (Cl. 143-5133) numeral I0 and which is or may be a unit casting presenting an overhang at the top and having a flanged base for the reception of securing bolts II. The over-hang is drilled to provide a vertical bore, and there is also provided a horizontal bore located adjacent the base of the standard, with each of said bores being press-fitted with bushings, as I2, and having the usual lubricating `felts I3 fed by an oil cup I9. Journaled in said bushings, and arranged for reciprocal sliding movement and for rotary movement, respectively, there is provided a spindle I4 and a drive shaft 2 I5 with the shaft receiving its drive by means of a belt I 6 passing about a pulley II and driven lfrom a suitable source ,of rotarypower such as an electric motor (not shown). The shaft pro-- jects by its frontal end forwardly beyond the standard and upon this protruding end and secured by a set screw or the like thereto isa iiywheel I8. Crank action is transmitted from this ywheel to a connecting rod 20 finding oiset pivotal attachment to the face of the wheel, and the other end of the rod connects as at 2I with the lower end of the reciprocally movable spindle.

Designated 22 is a work-supporting table surmounting the standard, and this table, while it might feasibly be producedas an integral part of thestandard, is desirably made removableand is composed of a steel plate having a severality of depending hollow legs 23 welded to its underside through Vwhich securing bolts 24 are passed to secure the table in position. The table has a central aperture 25 arranged to lie in perpendicular alignment with the slide axis of the spindle, and the legs, shown as being three in number, occupy positions equidistantly spaced at intervals of a circumference taken concentric to this axis. The spindle is made hollow at its upper end to describe a socket having a square 'shape in cross-section, and this hollowed extremity, by reciprocal movement of the spindle, works within the space lying between the top of the standard and the bottom of the table. Denoted 26, the saw-blade of the machine likewise has a square shape in cross-section and fits snugly by its lower end Within said socket, being firmly secured to the spindle by a set-screw 21 accessible through the openings between the legs. In forming the teeth of the saw-blade, the latter is cut to give to each of the four sides of the blade a sharpedged fluting, and these fiutes, which extend transverse to the blades length, are by preference made to register the fiutes of one side with the flutes of adjacent sides. The teeth themselves are desirably of the buttress type, and which is to say teeth of which one face is disposed perpendicular, or nearly perpendicular, to the axis of the blade while the other face is inclined to such axis. In mounting the saw-blade, the same is applied such that the abrupt faces lie upon the underside of the teeth, thus performing the cutting function by the down-stroke of reciprocation. Distinguished from jig-saws as they have been heretofore designed, and namely such as provide top and bottom guides for the saw-blade and hence require that the blade be of a predetermined length with connector devices at each of the two ends, the saw-blade of the present invention is attached only at one end and the length is unimportant other than for a self-evident necessity that the upper extremity extend above the level of the table-supported work. In consequence thereof, it becomes possible to supply to the user a blade somewhat longer than would normally be required and as continued use of the blade eventually dulls the comparatively few teeth which, in any jig-saw, perform the actual work'of sawing, the operator need only out off a vshort section from the lbottom 'end of the blade and thus enable the blade to be lowered to the extent necessary to bring a fresh series of teeth into the cutting zone. In lieu of cutting off a section of the blade, the spindle could, perforce, be hollow throughout its length and consequently allow the blade to be pushed downwardly into the socket as successive series of teeth become worn.

The manner by which my square-sectioned saw-.blade allows the operator to work along a given saw-cut and, reaching a sharp-angled turn, .change direction .and then work in a Ydirectionangular to the former'lineV of travel will, it V.is thought, be clearly understood, the teeth upon .one Vside of the blade performing the cutting `function as the vblade traverses one said saw-.cut and the teeth upon an adjacent side of the blade thereupon picking up the work as ithe directive travel changes. Where the Vturn in question vis a right-angled turn, Vit becomes unnecessary to turn the work in any degree .what- Soever, .the operator simply imparting to the work in a directive movement at right angles to .the vprevious line of movement. For negotiating turns other than a right-.angled turn, the degree to which ,the work must .be turned is at most 45 due to Ythevfact that two cutting faces removed 90 from one anotherare alwaysavailable. It should be here pointed out .that a threesided blade -could be employed in lieu -of the squareblade which Ihave illustrated, and while a blade of thisform would .be less desirable the same would suffice to give to the blade thenecessary rigidity which enables Vthe present machine to eliminate -the objectionable top guide which is common to previous jig-saws, and with its `teeth on all three sides would allow sharp-angled turns to be accurately negotiated,necessitating,

,4 however, somewhat greater maneuvering of the work.

The invention, the manner of its employment, and its accomplishments are believed to be clearly understood from the foregoing. While having illustrated and described my now-preferred embodiment, modifications may obviously be resorted Without departing from the spirit of the invention and it is my intention that the here- .to annexed claims be read with a scope fully commensurate with the broadest interpretation which the employed language fairly permits.

What I claim is:

1..A iig-,Saw blade produced from sectionally square stock of uniform gauge throughout its length and .formed upon each of the sides with .a series of uniformly spaced buttress-type transverse teeth so located, as between the teeth of the several sides, that each of the teeth of a respective said side exactly register with the 4teeth `of the two adjacent sides,-the surfaces of .the blade which .are donned between .the suce .cessive .teeth defining substantial iacets of an isosceles trapezod :sha-pe. v

2. The jig-saw blade o f `clairn- 1 in which `the lnon-parallel sides of said isosceles trapezoid facets are substantially longer than the shorter of the two parallel sides.

ALVIN NORQUIST. i

References Cited in the le of this 'patent UNITED STATES PATENTS 

